Steering "feel" question for the veterans

Back in May I picked up a '69 A108 from a guy in Santa Cruz. I've been slowly chipping away at it, starting with front disk brakes, then new wheels and tires. I've gotten the electrical all sorted and the (V8) engine runs pretty well. Currently working on installing all new seating. Anyway, I took it to the frame and axle shop last week for a full overhaul. Got new shocks, new kingpins, new u-bolts, new shackles, the works. Picked it up Friday, and I as drove away, I was surprised to find that there was still about 20˚ of freeplay in the steering wheel. This was the main reason I took it in for service in the first place. When I spoke to them prior to picking it up, they said the steering box was in good shape. I talked with the guy that worked on it about the play, and he said it felt good to him, but that it was probably mostly in the tires (which are 205/75-15). I talked with some guys at work that know old cars, and they said I should have an adjuster screw on the steering box to take out the slop. This afternoon I crawled underneath and found the screw and tightened it up. It definitely took out the freeplay, but the steering still isn't what I'd hoped for. In particular, the van is hard to control over about 55 mph. It wanders quite a bit and takes almost constant steering input to keep it straight. Makes it very hard to relax cruising down the highway. So here are my questions:

Is it possible to get these old vans to track well at highway speed? Would wider, lower-profile tires help? Would a higher ratio (power) steering box help? Is there an ideal toe setting? Assuming that all the steering and suspension parts are in good working order, what needs to be fixed here?

my toe adjustment was way out when i first bought mine it handled like crap, you cold never take your hand off the wheel and it wondered all over the road, i used a tape measure and measured across the front of the front tires then measured across the back of the front tires, mine was toed out 2'' inches, i adjusted the tie rod so i had the same measurements. now it handles very well, but these old girls werent built to run 70, i never take mine past 55,

Tightening the adjustment screw must be done correctly so you don't mess up the steering box.
Follow the procedure in the service manual. Also check the gear lube in the box.

As for the wander at speed, you can make a big difference by an alignment. This adjusts

Camber = angle in degrees of the front tire from the bottom middle to the top middle viewed from the front. This affects pull at all speeds. It is usually different side-to-side to compensate for road crown (the middle is higher, the curb is lower for drainage). To fix this on a straight axle, the axle must be bent.

Toe-in = making sure the tires are both straight ahead, with a small amount (1/8") added to allow for compressing the tie rods ends. This will mainly affect how much effort is needed to move forward, and if toed out will also affect directional stability. It will want to 'dart' into corners with little input. Autocross guys will do this since the course is rarely straight. It will tear up tires quick! This is adjusted by changing the length of the tie rod.

Here is a picture showing toe and camber from the front.


Caster = this is the amount of angle the kingpins are set top to bottom looking from the side. It is the one that is affected by big and little tires (stagger) or any nose down rake and is responsible for straight tracking and the steering wheel coming back to center after coming out of a turn. I'd guess this is the big issue and is corrected by angled shims between the springs and the axle to 'lean' it back on top.  
Hereis a drawing of caster. Just consider the top and bottom ball joints as the top and bottom of the kingpin...


Picture of an axle, spring and a shim at the junction of them, tilting the axle. Note at the bottom of the springs the shim is thick at the left and thin at the right.


Get it to a good alignment shop that handles big trucks (straight axles like our vans) and have them do a full alignment.

Camber should be 1-1/2 degrees.
Toe-in should be 0 to 1/8"
Caster should be 5-1/2 to 6-1/2 degrees.
I had to add 5 degree shims to my Yellow van to get back the caster, which required longer u-bolts (special order).

 Everyone is totally correct above! What u didnt say is =does this van have power steering?? i will add = from experiences- i always try & find a good old guy-that does front end alignments for many years & does motor homes & sometimes big trucks-as they usually always have straight axles!! These people have usually forgotten things that all new alignment types have never been taught or experienced!! They know the buisness of doing our vans axles!! also=as in the old car owners circles @ car meets about who many go to or recomend?? also know when these cars were built new -they had -NO!! steering problems & went at many speeds & on some bad roads also! They didnt have steering problems. The only add'l thing ive ever seen or needed for any straight front axle was a steering shok kit for a bump-steer condition-i installed 30++ years ago & its still working great today ! =Find the old alignment man in the area!! 

Thanks to all. The shop I used was indeed one of those old-time, big truck frame and axle shops. They are willing to make any needed changes, so I think I will have them confirm the alignment based on the manual specs and the recommendations here. The caster is probably the culprit. Mine doesn't have power steering, but I was wondering if all the turns lock to lock of the manual steering was contributing to the poor feel and inherent sloppiness.

My background is motorsports. I'm used to running a few degrees of negative camber and toe out on my daily drivers. I have several national championships in the SCCA RallyCross program and have been competing in cars for over 20 years. I recently "retired" from racing to spend more time with my family, and the van is part of that plan. Wife and son are both totally loving the van rides.

I agree with Twinpilot001 that these things were once solid and predictable, so it should be possible to get that back. In the meantime, I'll take another shot at figuring out how to post pictures here, so I can share my progress. I know we all like seeing others' efforts.

if your caster is different from one side to the other it will want to pull in one direction, make sure if they go to bend your axle to set the camber thay dont use heat, it has to be bent cold with the correct porta-power

Ken, sounds like you have a good grasp of what is needed then.
The steering is a recirculating ball, not a rack & pinion. It will never be sports car quick, but with tight, lubricated parts, you should get it decent. Have them check the box and the drag link. Those are the most common parts to cause excessive steering play.

I still will bet on too little caster being a big contributor to the driving issue.

The specs I typed in are from the manual, so they should get you in the ballpark.

Strangely, my new boss also has an SCCA background and is spending more time with family.
Part of my job is building a couple of his cars back together. Yes, I'm diggin' it.

As promised, here are some pics of the van:







Mazda Miata seats in the front



70s Chrysler van seats in the back



Yours truly at the wheel. (Also 1969 vintage)



Photoshop image of my vision for the van. Planning to use root beer brown of the bass boat metal flake variety.

LOOKS REALLY SOLID, LOVE THAT BROWN CANT WAIT TO SEE IT PAINTED,

SHARP looking Van!!!! Some of us will disagree but I have always had the best luck on our alignment machine with the older cars setting the front end about 1/8 toed out on both sides to keep it from darting around at higher speeds my van will Cruze at 70 all day long and I have never had any tire wear complaints from our customers in all years of doing alignments... It also helps out with the crowns in the roads !!!! Different tire sizes will not cause play in the steering wheel just make sure the steering box NOW isn't adjusted to tight. .. My guess is you need to toe it out some.!!! 1/4 total toe out........

most people thing theres a problem with the alignment, and most of the time its shifted belts in a tire,

Usually when a belt has shifted in a tire up front it will shake the steering wheel and get worse the faster you go or you will have a very hard constant pull that will eventually start shaking before the tire comes apart..

A while back i posted almost the same question / problem. Many of the responses were similar to those posted on this question, all good info. So I took my van to an old time frame shop in carson city nv. After a road test and checking all of the componenets, all new, they figured out the I beam front axle was in 180 degrees off. Looking at the axle it appears the king pins are perfectly vertical however they actually have about 1 1/2 degree angle to them. I removed the front axle assembly and reinstalled it the way it was intended to be installed and the steering wander was almost completly cured. Only thing left to do now is to take it back to the alignment shop, for a final check and adjustment.

,,,,,Were the caster shims installed and in correctly?

Yes the shims were installed correctly. However the axle installed backwards effectively caused a 3 degree error in the caster. Now with the correct position of the axle and the shims the caster is where it needs to be.

here's to hoping you guys get it fixed up. I had a '72 CJ5 one time that would run all over the road, the pucker factor was high when it caught a rut.

slowflapper wrote:here's to hoping you guys get it fixed up. I had a '72 CJ5 one time that would run all over the road, the pucker factor was high when it caught a rut.

Reminds me of a Jeep that came into the shop for a quickie oil change.
When it was lifted, the whole front axle stayed on the ground way too long.
Found out both front shackles were broken! Guy was real lucky he came in for the LOF!